The objective of this grant is to develop practical tools for improving thermal dosimetry for hyperthermia. Two major themes unite the several specific tasks. The first is the use of experimental and theoretical models to improve thermal dosimetry. The second is that of establishing practical methods of characterizing heating systems and then incorporating them into computerized treatment planning and evaluation programs. Three experimental thermal models will be investigated. The in vivo kidney model with controlled perfusion will continue to be used to evaluate systems. This model will be extended by developing techniques for relocating it to other anatomical sites so that additional heating configuations can be evaluated. An entirely artifically perfused experimental thermal model will be developed as a "best case/worst case" tool for practical evaluations of equipment and programs prior to animal and human trials. Both the in vivo kidney and the artificial model will be compared with the Holmes, et al. in vitro kidney model. Electromagnetic heating apertures can be represented by an analytical model: the Gaussian beam. Individual apertures will be scanned and fitted to this model. This model then will be used in treatment planning and evaluation programs. Similarly, specific regional electromagnetic heating devices will be characterized experimentally and procedures developed for incorporating the measured parameters into the treatment planning programs. Analytical and numerical approaches will be investigated. The theoretical models will be verified by the experimental models. Conversely, the measurements on the latter will be extended and interpreted in terms of the former. We are continuing the development of an interactive, patient specific, machine specific three dimensional treatment planning program based upon imaging systems (e.g. CT).